Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual é o Userpics Free, quando o custo mensal para a conta paga é "desconhecido" e quando o usuário registrado é 2340?
 ###Tabelas: CREATE TABLE submissions (submissions_id AUTO_INCREMENT PRIMARY KEY, Year (Ceremony) VARCHAR, Film title used in nomination VARCHAR, Title in the original language VARCHAR, Director VARCHAR, Result VARCHAR) CREATE TABLE general_information__&__feature_comparison (general_information__&__feature_comparison_id AUTO_INCREMENT PRIMARY KEY, Name VARCHAR, Year Began VARCHAR, s Registered user VARCHAR, Updated in past 30 days VARCHAR, Registration VARCHAR, Ability to syndicate off-site feeds VARCHAR, Userpics Free VARCHAR, Userpics Paid VARCHAR, Monthly Cost for Paid Account VARCHAR, Yearly Cost for Paid Account VARCHAR, Permanent Account VARCHAR) CREATE TABLE overall_results_in_clt20 (overall_results_in_clt20_id AUTO_INCREMENT PRIMARY KEY, Year VARCHAR, Matches VARCHAR, Wins VARCHAR, Losses VARCHAR, No Result VARCHAR, Success Rate VARCHAR) CREATE TABLE doubles_finals_6–2 (doubles_finals_6–2_id AUTO_INCREMENT PRIMARY KEY, Outcome VARCHAR, Date VARCHAR, Tournament VARCHAR, Surface VARCHAR, Partner VARCHAR, Opponents in the final VARCHAR, Score VARCHAR) CREATE TABLE grands_prix (grands_prix_id AUTO_INCREMENT PRIMARY KEY, Round INT, Grand Prix VARCHAR, Pole Position VARCHAR, Fastest Lap VARCHAR, Winning Driver VARCHAR, Winning Constructor VARCHAR, Report VARCHAR)  
SELECT Userpics Free FROM general_information__&__feature_comparison WHERE Monthly Cost for Paid Account = unknown AND s Registered user = 2340